A variety of flooring products are widely used. Of these, a plywood flooring for an under-floor heating system having small dimensional deformation is known, which is produced by laminating one or more natural wood veneers to each other to form a waterproof plywood as a base, integrally forming a natural veneer on the base by using an adhesive, and coating a surface treatment agent, such as urethane acrylate, on the natural veneer to form a surface treatment layer.
The conventional plywood flooring for an under-floor heating system is produced simply by laminating a veneer on a plywood and coating the surface of the veneer in order to maximize the natural texture of the plywood flooring. However, in the case where a heavy or sharp object drops onto the surface of the plywood flooring, damage to the surface, such as indentation, is observed due to limited physical properties of the natural veneer.
In addition to the plywood flooring, there is known a laminate flooring product comprising an MDF or HDF layer as a base, a printed layer impregnated with a melamine resin formed on the base, and a surface treatment layer made of melamine formed on the printed layer.
However, since the conventional laminate flooring uses a thermosetting melamine resin as a surface material, the surface is likely to be brittle. Accordingly, when a sharp or heavy object having above specified load drops onto the laminate flooring, the impact site is partly damaged, e.g., broken or indented.
In addition, since the conventional laminate flooring uses a melamine resin as a surface material, the dimensional stability is poor due to ambient atmospheric conditions, e.g., moisture and temperature. To compensate for poor dimensional stability, an additional balance layer must be formed on the bottom surface of the laminate flooring, result in a structural disadvantage.